Use these options to specify how the date range returns results. "Exact" means that the start and end dates of descriptions returned must fall entirely within the date range entered. "Overlapping" means that any description whose start or end dates touch or overlap the target date range will be returned.

Two photographs showing surgical exposure of a section of the spinal canal, held open by long sutures, the upper showing a partially opened elongated cyst, the lower showing in addition forceps grasping removed cystic material.